Plant transposons: contributors to evolution?
A spectrum of different hypotheses has been presented by various authors, from plant transposable elements as major agents in evolution to the very opposite, transposons as mainly selfish DNA constituting a genetic burden for the organisms. The following review will focus on: (1) a short survey of the two main different assessments of transposable elements (TEs) concerning the origin of species (selfish vs useful DNA); (2) the significance of the hierarchy of gene functions and redundancies for TE activities (selfish in non-redundant parts of the genome, but as a source of variability in the rest); (3) the relevance of the results of TE research in Zea mays and Antirrhinum majus for species formation in the wild (contrast between artificial and natural selection); (4) three areas of research where a synthesis between the two different evaluations of TEs seems possible: regressive evolution, the origin of ecotypes and the origin of cultivated plants; and (5) some possible prospects regarding TE-induced species formation in the angiosperms in general, i.e., the basic difference between systematic and genetic species concepts and the conceivable origin of a large part of angiosperm morphospecies owing to loss of function and further mutations by TE activities.
Lönnig
W E
WE
Max-Planck-Institut für Züchtungsforschung, Köln, Germany. loennig@mpiz-koeln.mpg.de
Saedler
H
H
D004247:DNA; D004251:DNA Transposable Elements; D019143:Evolution, Molecular; D010944:Plants / Q000235:genetics*
D004251:DNA Transposable Elements; D004247:DNA